It appears that you are either running an old version of UNIX OS or you have a stripped down version.
Please show us what version of the UNIX OS you are running, that should help a great deal.
I believe that your "problem" lies with the OS version, not having the latest version could be the reason you dont have all the commands. Although it must be a rather old version of UNIX for this to be the case. Someone else in my office has a few boxes that don't have several commands because their OS is 10 years old, a version of BSD.
It may be something quirky - i..e the commands are stored somewhere else. I was going to suggest using 'find' to locate them....but that won't help! You shuold have a around for these at some other location.... then add that location to your path.
They may of course not be there...either as KM has suggested an older or different version - or because some fool deleted them!